Domain: x is greater than or equal to 7
Range: y is greater than or equal to 9
I've done the first four questions. Use this method to answer the rest. For an odd number of objects find the cost of one and multiply by how many you are asked to find.
3(2x + 4) = -6
6x + 12 = -6
6x = -6 - 12
6x = - 18
x = -18/6
x = -3